1. Field of the Invention
The present invention relates to a system for predicting a demand for repair parts in future.
2. Description of the Related Art
With respect to a product, the number of existing products in future can be predicted roughly from statistics in the past, and a market scale in the future of repair parts of the product can be obtained roughly by multiplying the number of existing products by a presumed exchange rate of the repair parts. The exchange rate is that for repair and approximately equal to a trouble rate.
However, with respect to a functional part, the trouble rate thereof cannot be obtained theoretically. Therefore, the parts have been manufactured based on a prediction of market scale that was obtained by experiences or perceptions of experts.
Therefore, accuracy of the predicted trouble rate is very low and the degree of confidence of the predicted demand is poor, so that the number of the repair parts manufactured based on such prediction is not suited to actualities. As the result, stock of the repair parts becomes excessive or short.
The present invention has been made in view of the foregoing, and an object of the invention is to provide a system for predicting a demand for repair parts in which trouble rate in the future of the repair parts can be presumed accurately and a reliable demand prediction is possible.
In order to achieve the above object, the present invention provides a system for predicting for a demand of repair parts comprising: a database that collects data of number of troubles, causes of troubles and number of years that have elapsed with respect to a certain kind of repair parts on the basis of the repair parts exchanged owing to troubles within a guarantee period; summing up means that extracts from the database troubles owing to durability deterioration from the causes of troubles to sum up the number of troubles owing to durability deterioration for each year that has elapsed; yearly trouble rate calculating means that calculates a trouble rate of the repair parts for each year that has elapsed from the number of troubles summed up for each year that has elapsed and from the number of existing products for each year that has elapsed; trouble rate presuming means that presumes a trouble rate of the repair parts after the guarantee period has elapsed from the calculated trouble rate of the repair parts for each year that has elapsed; and market demand predicting means that calculates a market scale in future of the repair parts from the presumed trouble rate of the repair parts after the guarantee period has elapsed and from a presumed number of the existing products in future to predict a demand for the repair parts; wherein the summing up means, yearly trouble rate calculating means, trouble rate presuming means, and market demand predicting means constitutes a computer.
Since about 100% of the parts getting out of order within the guarantee period are exchanged free of charge, a substantially accurate trouble rate can be obtained based on data regarding the repair parts exchanged owing to troubles within the guarantee period.
Among causes of troubles, causes owing to initial quality poorness are those peculiar to an initial period and will not cause trouble after the guarantee period has elapsed. Therefore, if troubles owing to durability deterioration except for the initial quality poorness are extracted as basic data, an accurate trouble rate can be calculated.
If such an accurate trouble rate within the guarantee period is calculated for each year elapsed, a trouble rate after the guarantee period elapsed can be presumed accurately, and a market scale in the future of the repair parts can be calculated from the trouble rate and the presumed number of the products existing in the future to predict a demand for the repair parts accurately.
In the above-mentioned system for predicting a demand for repair parts, the trouble rate of the repair parts after the guarantee period has elapsed may be presumed by the trouble rate presuming means that makes a Weibull-analysis of the trouble rate of the repair parts for each year elapsed.
Since distribution of life times (trouble times) of articles goes roughly along the Weibull distribution, the trouble rate after the guarantee period has elapsed can be presumed accurately by making the Weibull-analysis of the trouble rate of the repair parts for each year elapsed.